Branch/editor optimization (Redmine issue #2731)

@allisoncorey and @eric79 : Tagging you two to take a look at a pull request for issue 2731.

Core issue was performance hit from the editor tab. Initial thoughts were that parsing every set value when received was the cause, added in a buffering system to only store the raw data and only parse when the actual tab values were displayed.

Still had performance issues from the editor tab, even after it was closed with the new changes.  Further testing showed that displaying (even if no events were hooked to them) the large number of buttons on the editor tab that resulted from rendering the events for a VWF object seemed to be another significant performance culprit.  Even rendering the buttons but disabling any JS events being registered from them, produced this performance impact (even if the tab was hidden at the time).  Added in functionality to clear the div that contains these buttons when closed. Tested that things are properly re-rendered when opened after this clear, tested that the performance hit was gone when the editor was closed.

Performance hit from rendering buttons should be investigated further, but for now editor is optimized to avoid performance impacts when it is closed.